Sterilizer heater



April 14, 1925.

J. C. WOODSON STERILIZER HEATER Filed Dec. 2, 1922 aw w WITNESSES:

INVENTOR Jbmes C Woodson.

ATTORNEY Patented Apr. 14, 1925e UNITED STATES PATENT OFFICE.

JAMES C. WOODSO'N, OF EAST PITTSBURGH, PENNSYLVANIA, ASSIGNOR '10 WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIL- STERILIZER {HEATER Application filed December 2, 1922. Serial- No. 604,498.

To all whom it may concern:

' Be it known that I, JAMES C. Woonson,

a citizen of the United States, and a resident of East Pittsburgh, in the county of Allegheny and State of Pennsylvania, have 1nvented a new and useful Improvement in Sterilizer Heaters, of which the following is a specification. I

My invention relates to electrically heated devices and particularly to electrically heated sterilizers. I R

The object of my invention is to provide a relatively sim 1e, compact and inexpensive electric heater fbr a sterilizer.

In practicing my invention, I rovide a metal fluid container, having a spending flange portion, with a plurality of heating elements located closely adjacent to the bottom of the container and within the depending flange portion. Each heating element comprises a refractory brick or block having a lurality of iral grooves in its upper sur ace, within w ich is located a resistor member. An annular internallyshouldered supporting-member is provided for each of the refractory bricks and is supported by metal angle bars whose ends are secured against the inner surface of the de pending flange portion. A plurality of a0 manually operable switches are provided to permit of varying the energization of the eating elements.

Inthe drawings, Fi re 1 is a view, in side elevation, with certaln portions cut away, of a fluid container with which is associated an electric heater embodying my invention,

Fig. 2 is a top plan view of an electric heater assembly embodying my invention,

Fig. 3 is a view, in vertical section, of one of the heating elements, taken on the line IIIIII of Fig. 2,

Fig. 4 is a diagrammatic representation of a reslstor member, and 1 Fig. 5 is a dia ram of connections employed with the evice embodying my invention.

A fluid container 11 is represented as an flange portion 14. The to and the bottom are secured to the body of t e tank 11 in any suitable or desired manner.

. Within the depending flange ortion 14 is located aheating element assem 1y 15 which comprises a plurality of refractory bricks 16 located in and supported by annular metal supporting members 17 which have integral and radially extending feet 18. The refractory bricks 16 are provided with a plurality of spirally extending grooves 19 in the upper surface thereof Within which is located a suitable resistor member 21. The annular members 17 are each provided with an internal shoulder portion '22 to permit supporting the bricks 16 substantially as illustrated in Fig. 3 of the drawing.

A plurality of angle bar members 23 of relatively short length and an intermediate angle bar member 24, of eater length, extend in parallel, spaced re ation between the inner periphery of the depending flange portion 14. Supporting angle members 25 mechanically connected against the inner surface of the flange portion 14 and to the ends of the members 23 serve to hold the angle bar members 23 in a predetermined position vertically of the depending flange portion 14. Substantially similar angle members 26 hold the ends of the member 24 and are secured against the inner surface of the flange ortion 14, the three angle bar members being located in substantially the same plane. The integral feet 18 of the respective supporting members 17 rest upon and are secured against the respective angle members by screws 27.

The angle bars 23 and 24 are so located that the upper surface of the bricks-16 is relatively close to the lower surface of the bottom 13 of the container in order that the distance which the heat must traverse shall be as short as possible.

A metal reflector plate 28 is located beneath the heating element 15 and comprises a dished member which is suitably supported by .the depending flange ortion 14 to which it is secured in any suitafiile or desired manner.

In Fig. 5 of the drawing, I have illus- 0 sired to operate at trated a three-wire supply circuit and a single pole, single-throw switch 29, together with a single-pole double-throw switch 31 for selectively and variably controlling the energization of the resistors 21. The refractory bricks l6 and the resistor member 21 located therein are substantially standard articles of manufacture and are arranged as hereinbefore described in order to permit of employing with each of said resistors a multi-heat switch.

In the device as actually installed, the two parts of each of the resistor members 21 are permanently connected in parallel circuit relation by conductors 32, as illustrated in Fig. 5 of the drawing. One of the outer supply circuit conductors is electrically connected by a conductor 33 to a lower contact terminal 34 of the switch 31. The upper contact terminal 35 of the switch 31 is connected by a conductor 36 to the mid dle one of the supply circuit conductors. The intermediate terminal of the switch 31 is connected to one of the outer terminals of the upper right hand resistor 21, by a conductor 37, and is at the same time connected to a contact terminal 38 of the switch 29 by a conductor 39. The switch blade of the switch 29 is connected by a conductor 41 to the outer terminal of the lower right hand resistor member 21. The other supply circuit conductor is connected by a conductor 42 to the outer terminals of the upper and the lower left hand resistors 21. The intermediate terminals of the resistor members 21 located diagonally oppositely to each other are connected by the re spective conductors 43 and 44.

If it is desired to operate at a maximum heat, the blade of the switch 31 is so moved as to engage the terminal 34 and the blade of the switch 29 is so moved as to engage the terminal 38. With the switches in these positions, a circuit is established from one of the outer, supply circuit conductors through conductor 33, the blade of switch 31 and through a circuit comprising the conductor 37 \and the upper right hand and the lower left hand resistor members to the other supply circuit conductor of the 220 volt circuit, while, at the same time, a circult is established through conductor 39, switch 29, conductor 41 and through the resistors of the lower right hand and the upper left hand heating element to the same supply circuit conductor.

If it is desired to operate at substantially heat, the blade of switch 29 is so moved as to interrupt the circuit therethrough wherebyonly one of the hereinbefore men tioned circuits is established. If it is denormal input or heat the blade of switch 31 is so moved as to engage the contact terminal 35 and the blade of switch 29 is so moved as to engage the terminal 38. This establishes substantially the same circuits as hereinbefore described between the resistor element-s themselves but connects them across the lower two of the three supply circuit conductors between which there exists a potential difference of 110 volts only. If it is desired to operate at substantially normal energy or heat, the circuit through switch 29 is interrupted whereby only oneset of resistor elements is connected across the 110 volt circuit.

By manipulating the switches as hereinbefore described, it is therefore possible to obtain what may be called a normal or full heat, A heat, A heat, and heat respectively, whereby a relatively large range of heating effects is obtained. The location of the switches 29 and 31 may be any suitable 01' desired one and has not been indicated in the drawing as it forms no part of my in vention.

Various modifications and changes in de tail and arrangement may be made without departing from the spirit and scope of the invention, and such modifications are intended to be covered by the appended claims.

I claim as my invention:

1. In an electrically heated device, the combination with a fluid container having a depending flange portion, of a plurality of parallel-extending, spaced bars having their ends secured to said flange portion, a plurality of metal supporting members secured on and supported by said spaced bars, refractory bricks supported in said metal supporting members and resistor members in said refractory bricks supported thereby closely adjacent to the bottom of said container.

2. In an electrically heated device, the combination with a container having a depending flange portion, of a metallic framework secured to said depending flange portion, a plurality of metal supporting members secured on and supported by said frame work, a plurality of heating elements located in and supported by said metal sup porting members closely adjacent to the bottom of said container and a reflector member below said heating elements supported by said depending flange.

3. In an electrically heated device, the combination with a fluid container having a flange portion extending below the bottom thereof, of a plurality of refractory resistorsupporting members located closely adjacent to and beneath the bottom of said container and having grooves in their upper surface, a resistor member located in said grooves, a plurality of internally flanged metal supports for holding said refractory members, a plurality of parallel-extending angle bars having their ends secured to said flange portion for holding said metal sup ports, and a metal reflector having an up wardly extending concave surface supported by said flange portion below said metal supports.

' 4. In an electrically heated sterilizer, in combination, a fluid container having a flange portion extending below the bottom thereof, a plurality of selectively and variably energized electric heating elements, located below and closely adjacent to the bottom of said container, and means opera tively secured to said flange portion for re ducing heat loss from said heating elements in a downwardly direction.

In testimony whereof, I have hereunto subscribed my name this 27th day of November 1922.

JAMES C. WOODSON. 

